1. Field of the Invention
This invention relates generally to a device for illuminating reading material. More specifically, this invention relates to a light source which can be clipped onto a book or other reading material. The light source contains a timing device which the user may set so that the lamp which provides the light turns off after a selected number of minutes so that, if the user falls asleep without turning off the lamp or otherwise forgets to turn off the lamp, the lamp will not burn indefinitely.
2. Discussion of the Related Art
Applicant is unaware of any booklight having all the features and aspects of the present invention.
The following prior art is known to applicant:
U.S. Pat. No. 5,997,165 to Lehrer discloses a reading light source which the user wears about the head. The illumination source is in a separate unit. The light travels to a remote lamp via a fiberoptic cable. The present invention differs from the teachings of Lehrer in that, in the present invention, the light source clips to the reading material and there is no remote illumination source. Further, the present invention has a countdown timer to shut off the device, a feature which is not taught by Lehrer. Lehrer also does not teach a rotatable coupling by which the lamp can be rotated.
U.S. Pat. No. 4,283,661 to Doty discloses an ultraviolet or infrared irradiation apparatus with a detachable timing mechanism. Doty teaches the timing mechanism as a separate unit which is connected into the circuit which supplies power to the irradiation apparatus. The present invention differs from the teachings of Doty in that Doty does not disclose a lamp which can be used for reading. Doty teaches away from the present invention in that Doty warns the user about eye damage from the irradiation apparatus because the wavelengths of the radiation are harmful to the eyes. Further, Doty does not teach a device which can be clipped to a book or other reading material nor does Doty teach an integral shut-off timer. The irradiation apparatus of Doty is a large, floor-stand lamp as opposed to the small, portable light of the present invention. Doty does not teach a rotatable coupling.
U.S. Pat. No. 5,163,748 to Messinger discloses a clipboard which can be illuminated from a light source internal to the clipboard. The light source makes the clipboard itself glow. Messinger teaches that the clipboard has a clamp for holding reading materials. The clamp has a clock built into it. The present invention teaches a clip without any board. The clock in the teachings of Messinger is a time-of-day clock which performs no control function, that is, it is simply a clock attached to the clamp portion of the clipboard. This clock has no ability to shut off the light source while the present invention teaches a countdown timer which will cause extinguishment of the light source. The light source in Messinger backlights the material; the light source in the present invention lights the material from the front. If the material placed on the clipboard taught by Messinger is not completely transparent, the amount of light passing through the material is unsatisfactorily reduced. Thus, if completely opaque material is placed on the Messinger clipboard, no light will pass through the material and the material can be read only by that small percentage of the light that leaks out from around the edges of the clipboard or the material. In the present invention, the degree of transparency is irrelevant to the amount of light falling on the material. Messinger does not teach a rotatable coupling.
U.S. Pat. No. 5,469,346 to Haut et al. discloses a signaling lamp to be used by hunters and others so the users can find a hunting location in the dim or nonexistent daylight of an early morning. The hunters place the lamp at a desired hunting location the night before that morning. Haut teaches a lamp with a clock which can be set to turn on at a specified time so that the lamp need not emit signals all night long. The lamp taught by Haut has a normal flashlight capability not connected to the timer. Haut teaches a lamp with a slidable cover which, when opened, reveals the section which will emit the signals. This signal is not intended to give the level of or period of constant illumination necessary for reading a book or other material under normal circumstances. The flashing can be quite irritating to someone trying to read. Haut does not teach any clip. Haut does teach a timer that will shut off the flashing light after a period of time. Haut does not teach a rotatable coupling.
U.S. Pat. No. 5,138,538 to Sperling teaches a home-use flashlight with self-extinguishing feature to prevent draining of the battery if the flashlight is left with its on-off switch in the on position. Sperling teaches that the flashlight will shut off after a period of time which, in some embodiments, the user may select or control. The present invention contains a clip which is suitable for clipping the light to a book or other reading material. Sperling does not teach any such clip. The absence of this clip means that the teachings of Sperling require the user to use both hands if the user needs to read something, one hand for the lightxe2x80x94which can move around relative to the materialxe2x80x94and the other hand for holding the reading material. The present invention teaches a light temporarily fastened by its clip to the reading material. Sperling does not teach a countdown timer nor a display of the time remaining before the light will shut off. Sperling does not teach a rotatable coupling.
U.S. Pat. No. 6,249,089 B1 to Bruwer discloses a battery-saving mechanism which shuts off power to a battery-powered circuit for brief durations of time. Bruwer teaches that the mechanism may be external to a battery or may be built into the battery. Bruwer teaches a mechanism which shuts off current when voltage in a circuit drops to or below a preselected level during which shutoff period a capacitor recharges the battery. Bruwer teaches a timer that turns the circuit back on after some preselected, short, unit of time and which may give the user the illusion that a flashlight using the teachings of Bruwer is constantly lighted. Under certain circumstances, the device may have a delayed shutoff function, but Bruwer does not teach a user-controllable countdown timer with a display for delaying shutoff nor any way the user can select the period before the current is shut off. There is no user accessible control device as taught in the present invention. It would appear that the delayed shutoff function taught by Bruwer is an outgrowth of merely leaving the current on until it falls below a certain level. Thus, the time before shutoff is a function of a variety of factorsxe2x80x94temperature, charge in the battery, etc.xe2x80x94all out of control of the user as opposed to the teachings of the present invention which give the user complete control over the time before shutoff. Bruwer does not teach a clip for attaching the flashlight to reading material. Bruwer does not teach a rotatable coupling.
An object of this invention is to provide a small, portable light which can be clipped onto a book or other reading material so that a user can read the material without need for illuminating an entire room or other area. A common situation involves someone reading in bed while another person nearby is asleep or trying to sleep. Confining a light source to the area of the reading material minimizes the disturbance that the light may create for other persons.
In addition, the disclosed invention is small and portable. That means that the light can also be useful in other situations. An example might be a passenger in an automobile reading a book or a map or instructions when it is dark outside. It is well-known that drivers may find it difficult to see the roadway when there is a significant source of light from within the automobile. The passenger using the disclosed invention helps the driver avoid having problems of visibility. The disclosed invention is superior to maplights often installed in automobiles in that it can be used by any person in the automobile, including back seat passengers, and armed in such a way that the amount of light perceived by the driver can be minimized.
In a further situation, the disclosed invention might be used where the user has no other light source available, such as when camping in the woods.
Previous solutions to the above problems exist. A common solution to the reading in bed problem is a small, high intensity lamp usually powered by an alternating current source. Such lamps lack portability and must rest on a table or nightstand or other surface. The disclosed invention has a clip which allows the user to clip the lamp to the reading material. This has the further advantage of keeping the light steady relative to the reading material no matter how much the user moves around in the bed or elsewhere. If the user happens to be walking, the light source remains on the reading material without any further intervention of the user.
The clip has the additional advantage of freeing the user""s hands for holding the reading material or for anything else the user wishes to do, such as adjust the volume on a radio or TV.
The disclosed invention has a further advantage in that it can be set to automatically shut itself off after a pre-selected number of minutes. It is common that persons reading in bed fall asleep before turning off the light. In such case, the light continues to burn until it is shut off or, in the case of battery-powered lights, the batteries run down.
Another advantage of the disclosed invention is that it is small so that it can be carried in a pocket, backpack, or purse, kept in a drawer or glove compartment, or left on a table without taking up much room. This small size has the further advantage of keeping the weight down so the disclosed invention does not increase the weight of the reading material to any significant degree.
It should be noted that the term xe2x80x9clampxe2x80x9d has two primary meanings herein. In reference only to the teachings of Doty, the term refers to an entire illumination apparatus. These apparati are often referred to as sunlamps and are not designed to provide visible illumination.
In contradistinction to its use in the teachings of Doty and in all other contexts herein, the term xe2x80x9clampxe2x80x9d is used as it is used by persons of ordinary skill in the electrical arts, namely, as roughly synonymous with what is vernacularly called a xe2x80x9clight bulbxe2x80x9d. A lamp, then, is something which emits visible light i.e. light which illuminates a surface to assist a viewer to see the surface when a sufficient current is applied thereto. A lamp is a component of an illumination device and not the illumination device itself.
The term xe2x80x9clightxe2x80x9d refers to illumination or light energy and not to any part of the disclosed device. Light is the product of an illumination device.